Concealed technology, visible architecture

ASP Architecture specialise in timber structures with high ecological added value. They received multiple awards for the design of social housing in the village of Plainfaing in the French area of Vosges.

As an architect, when do you get excited about a building?

Antoine Pagnoux: For me, architecture is good when it is accessible and adaptable, and when the ambitious choice of an efficient system using biobased materials is beneficial to the residents. The challenge is to conceal the technology, even if it is present in all aspects of the design, namely for reasons of environmental protection and living comfort.

„We did not want the technological accomplishment alone to dominate . The innovative technical solutions are hardly perceptible from the outside, they provide the benefits of passive house design at all building levels.” - Antoine Pagnoux, ASP Architecture Antoine Pagnoux

What is special about the project in Plainfaing?

The project involved the construction of social housing in the middle of a village directly on the high passes through the Vosges mountains. The aim was to integrate these apartments well into their surroundings, to emphasise their own distinctive identity without clashing with other buildings and to facilitate residents’ participation in the lively village community. In addition, we did not want the technological accomplishment alone to dominate the architecture Accordingly, although the innovative technical solutions are hardly perceptible from the outside, they provide the benefits of passive house design at all building levels.

Were there any particular challenges during planning or construction? How did you overcome them?

The challenge lay in facilitating all aspects of the everyday life of residents, but long-term financial viability was also important for the social housing association. Our solution takes all factors into account, including, for example, the materials, equipment and orientation.

Where did you get the inspiration for the design?

From our region! The monolithic design of the apartment block draws on the form of traditional Vosges farmhouses. And we selected the black and grey roof tiles with a matt glazed surface to invoke the patina of the old roofs and the shingle cladding that is common in this region. This building was intended to make both the functions and the structural nature of the project apparent. These considerations culminated in accurate precision work on the details of the façade.

Why did you choose this roof tile in particular? How did you come up with the idea of using the tiles not only for the roof but also for the façade?

The Koramic roof tile used on the roof and façade makes the façade as long-lasting as possible and, at the same time, is an ecological building material. The low maintenance required is a further advantage for the the social housing association. The ceramic tiles on the roof and façade lend a contemporary look to the simple, rational building exterior. In this way, we have created an apartment block that is brought to life by the reflections of the glazed elements.

What effects does the terracotta cladding have on the climate in the building and on its energy efficiency?

The role of the cladding is essentially to create a shell with an insulating effect that protects the walls against the external environment. With the exception of the covered entrances, where the wood – oiled larch – is exposed, the building is clad in tiles to shield it from bad weather. Moreover, ceramic building materials age naturally and retain their aesthetic effect.

Why did you choose this particular tile model?

We quickly opted for Wienerberger because of the large range of colours, but also because of the possibility of using corner roof tiles to achieve a continuous, monumental effect. The roof continues uninterrupted over the gable and onto the façade to underscore the monolithic impact. The roof tiles selected were Datura Ardoisé, Datura Noir matt glazed and Datura Gris Noir matt glazed. The colour varies depending on the height to create a gradient effect with light reflected by the glazed roof tiles.

What other materials were used in the building and why? What is special about the combination of materials?

The building is a passive house made of wood and straw. We favour locally produced materials and the use of prefabricated walls. Sustainable development is also conducive to a cleaner construction site with shorter construction times, even in regions with long winters.

How is the building insulated and what type of heating/cooling is used?

The 40-cm-thick layer of straw in the wooden walls ensures excellent insulation. There is also a centralised, double-flow VMC (controlled mechanical) ventilation system and heat recovery from wastewater. The system is rounded off by a central heating system with an air source heat pump, supplemented by individual wood-burning stoves.

Is a special approach required for social housing projects?

For housing associations such as Le Toit Vosgien, that are aiming for long-term profitability, the advantages of passive construction with high living comfort are undeniable: satisfied tenants resulting in lower tenant turnover, little building maintenance and very low energy costs (less than 15 Euro per month).

What is the social concept behind the idea?

This project made it possible for four new eligible families to move to the village and stimulate its social life with a building that will endure for 40 or 50 years without the need for modifications or refurbishment.

Congratulations on the many awards you were presented for this project! Does sustainability always pay off?

The awards show recognition of the work and commitment of everyone involved. I think that the key aspects of this project are the structural concept and the insulation value, combined with a simple and intuitive architectural approach. Projects of this kind have a further advantage that I would like to mention: the development of multifaceted interpersonal relationships between the experts. Everyone involved in the process speaks to each other more and works together better.